/**
 * Copyright 2009 Emory University
 * 
 * Permission is hereby granted, free of charge, to any person obtaining a
 * copy of this software and associated  * documentation files (the 
 * "Software"), to deal in the Software without
 * restriction, including without limitation the rights to use, copy, modify,
 * merge, publish, distribute, sublicense, and/or sell copies of the Software,
 * and to permit persons to whom the Software is furnished to do so, subject to
 * the following conditions: The above copyright notice and this permission
 * notice shall be included in all copies or substantial portions of the
 * Software. 
 * 
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO
 * EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES
 * OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
 * DEALINGS IN THE SOFTWARE.
 */
package com.markgrand.structuredSql;

/**
 * Trait for implementations of the {@link ColumnIdentifier}
 * class.
 * 
 * @author Mark Grand
 */
private[structuredSql] trait ColumnIdentifier extends SQLValueAppender with SQLIdentifier {
    /**
     * The unqualified name of the column identified by this object. 
     */
    val columnName : String

    /**
     * A string that uniquely qualifies that name that is the value of 
     * <tt>columName</tt> within the enclosing SQL statement. This can be
     * a table name or an alias defined within the SQL statement.
     */
    val nameQualifier: Option[String]
    
    /**
     * Append an SQL syntax compliant representation of this column identifier 
     * to the given StringBuilder object.
     */
    def append(builder : StringBuilder) {
        if (nameQualifier.isDefined) {
            appendIdentifier(nameQualifier.get, builder)
            builder.append('.')
        }
        appendIdentifier(columnName, builder)
    }

    override def toString() = {
        val builder : StringBuilder = new StringBuilder();
        append(builder);
        builder.toString();
    }
    
}
